Relation between cutting head and cutting quality:
When the center of the cutting head is not coaxial with the center of the laser, the influence of the center of the cutting head on the cutting quality is as follows:
1) affect the cutting, cutting gas injection, leads to uneven gas volume, thus cutting part is easier to melt on one side, on the other side there is no this kind of phenomenon, in the plate cut less than 3 mm, it has a little influence, in the plate cutting more than 3 mm, its influence is more serious, and sometimes can lead to can't cut.
2) Will affect the quality of acute angles.When cutting sharp Angle or small Angle workpiece, it is easy to appear local overmelt phenomenon.When cutting thick plates, cutting may not be possible.
3) Impact perforation.The perforation process is unstable and the time is not easy to control.The penetration of thick plate will lead to overmelt, and the penetration conditions are not easy to grasp, which has little influence on the penetration of thin plate.
Laser head aperture selection:
Aperture of the laser head is divided into 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm and so on.At present, nozzle aperture generally adopts 1.5mm and 2mm.
1) Thin plate below 3mm: the cutting surface with 1.5mm will be very fine;The 2mm cut surface will be very thick and the edges and corners will melt easily.
2) Thick plate over 3mm: Due to large cutting power and long relative heat dissipation time, the relative cutting time also increases.Use 1.5mm, small gas diffusion area, use instability, but basically usable.Use 2mm, the gas diffusion area is large, the gas flow rate is slow, more stable when cutting.
3) Diameter 2.5mm aperture, only suitable for cutting thick plate over 10mm.To sum up, the size of nozzle aperture seriously affects the cutting quality and perforation quality.At present, laser cutting mainly USES nozzles with diameters of 1.5mm and 2mm.
Therefore, the larger the nozzle aperture, the poorer the relative protection of the focusing mirror, because the spark of the molten material during the cutting process is more likely to bounce back, making the life of the lens shorter.
Concentricity between the nozzle center and the laser is one of the important factors affecting the cutting quality, especially when the workpiece thickness is larger.Therefore, the concentricity between the nozzle center and the laser must be adjusted to obtain a better cutting section.